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What's the pKa of the phosphate group in DNA and RNA molecules?
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+ Dna
+ Phosphates
+ Hydroxylation
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Posted by
Kaju Deka
What's the pKa of the phosphate group in DNA and RNA molecules?
Phosphoric acid, when free in solution, is a triprotic acid with pKa1 = 2.2, pKa2 = 7.2, and pKa3 = 12.4.But most of the phosphate groups in DNA and RNA molecules participate in phosphodiester bonds, thus only one of its hydroxyl groups are free to dissociate. Does anybody know the pKa for these phosphate groups?And phosphate groups at the 5' end have a phosphoester bond and two hydroxyl groups free to dissociate. Does anybody know the pKa1 and pKa2 for these terminal phosphate groups?
